Electric timepiece



Sept. 4, 1962 A. BEYNER ETAL ELECTRIC TIMEPIECE 2 Sheets-Sheet 1 FiledApril 19, 1960 IN VE N TOPS VI E N w m U N W n g 8mmv EBA E wmy ARDu p1962 A. BEYNER ET Al. 3,052,082

ELECTRIC TIMEPIECE Filed April 19. 1960 2 Sheets-Sheet 2 P/AE' H] AL 1 lIN VE'N TOPS ANDRE BEYNEI? RENE BES A TTOFPNEY United States Patent ()13,052,082 ELECTRIC TIMEPIECE Andre Beyner, Neuchatel, and Ren Besson,Les Loges,

Fontainemelon, Switzerland, assignors to Ebauches S.A., Neuchatel,Switzerland, a Swiss firm Filed Apr. 19, 1960, Ser. No. 23,276 Claimspriority, application Switzerland Apr. 20, 1959 8 Claims. (Cl. 58-23)The present invention relates to an electric timepiece.

This electric timepiece is characterised by the fact that a casing ringelectrically insulated from the frame of the movement surrounds thelatter and provides the electrical connection on the one hand betweenthe motor and one terminal of an accumulator enclosed in the case, andon the other hand between the said accumulator and a terminal forre-charging the latter, which terminal is mounted on the case in suchmanner as to be electrically insulated therefrom.

One constructional form of the subject of the invention is illustratedby way of example in the drawings, in which only the parts necessary foran understanding of the invention have been shown.

FIGURE 1 is a diagrammatic plan view partly in fragmentary form andpartly in section, of the movement of an electric timepiece,

FIGURE 2 is a fragmentary axial section through the timepiece with itscase, to a larger scale,

FIGURE 3 is a plan view of the movement plate, to a smaller scale, inwhich only its outer contour has been shown,

FIGURE 4 is a section through a detail along the line IV--IV of FIGURE1,

FIGURE 5 is an elevational view of a detail, partly in section, and

FIGURE 6 is a circuit diagram in which the main parts have beendiagrammatically represented, and which illustrates the principle ofoperation of the motor.

The illustrated timepiece is a wrist watch having a round movement. Thelatter comprises a circular movement plate 1 having a portion 1a oflarger diameter, as also an external lug 1b diametrically opposite thepart In (FIGURES l and '3).

The electric motor of the said watch comprises a stator having a core 2of horseshoe shape, which is terminated by two pole pieces 3a and 3b.The core is in turn formed of two ferromagnetic strips 2a and 2b (FIG-URE 4) bedded in a layer 4 of electrically insulating material. The corecarries an electric winding 5 formed of two parts separated by a sleeve6 mounted on the strips 2a and 212, at the mid-point of the latter. Thewinding is covered by a protective packing 7 of electrically insulatingplastic material, which has a substantially square external section,except at the location of the section line IV-IV, where the packing hasan internally extending projection 7a covering a resistance 8, thefunction of which will hereinafter be indicated. The stator is fixed tothe movement plate 1 by the lug 1b on the latter, which is introducedinto a recess corresponding to the packing 7, and by screws (not shown)which extend through holes 9a and 9b in the pole pieces 3a and 3b, fromwhich they are electrically insulated by insulating bushes 10 internallylining said holes.

The rotor of the motor comprises a movable armature formed of a disc 11of ferromagnetic material having four vanes 11a, 11b, 11c and 11d. Thedisc is mounted on the staff 12 of the balance wheel, which is not shownin FIGURE 1, but is diagrammatically represented at 13 in FIGURE 6. Itis to be noted that the bridges of the movement, which partially coverthe movable armature 11, also have not been shown.

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The driving pulses are controlled by thebalance wheel and an associatedswitch. Staff 12 of the balance wheel carries for this purpose a dog 14acting, in its passage, on two resilient switch blades 15 and 16 fixedto the plate 1 by means of an insulating stud 17 and electricallyconnected to the lead-out wire 18a of the winding 5 by a metal bar 19.It is to be noted that the bar is also insulated from the fixing screwof the stator, which extends through the hole 9a. When the dog 14 is incontact with either one of the resilient blades 15- and 16, it connectsto ground in common with one of the poles of an electric current source,as will hereinafter be described, and further connects with the lead-outwire of the winding 5. The current then flows through the winding insuch manner that the movable armature 11 is thus subjected to a pulse.It is to be noted that two pins 20 and 21 are in addition fixed to theframe of the movement, at a bridge (not shown) which extends over theblades 15 and 16. When the blades are deformed by the dog 14, one of theblades, depending upon the direction of movement of the balance wheel,comes into contact with one of the pins 20 and 21, whereby the groundingof these blades is further ensured. The motor drives the hands (notshown) through a normal mechanism, for example a lever, which also hasnot been shown, and which does not form part of the present invention.

The movement is surrounded by a casing ring 22 which bears on theinsulating packing 7 of the stator, so that it is not in electricalcontact with the frame of the movement. In order to avoid accidentalcontact, that portion 22a of the ring 22 which is situated opposite theportion 1a of the movement plate 1 is of larger diameter than theremainder of the ring 22. In addition, the external diameter of theportion 1a of the plate is smaller than the external diameter of theinsulating packing 7 of the stator. Consequently, a safety space 23remains between the plate and the ring 22. The ring has internalresilient lugs 22b bearing against a dome 24 of the envelope of anaccumulator 25 (FIGURE 2) lodged in the back 26 of the watch case. Thisdome constitutes one of the poles of the accumulator, the other poleconsisting of a dome 27 of the envelope, which dome is in contact withthe back 26, that is to say, with ground. An annular ring 28 is disposedbetween the dome 27 and the back to ensure electrical contact betweenthese two parts. The casing ring 22 has in addition an inner lug 22c(FIGURES 1 and 6) connected to the lead-in Wire 1812 of the winding 5.Thus, the electrical connection between the motor and the accumulator isensured on the one hand through ground and on the other hand through thecasing ring 22. It is to be noted that the resilient tongues 22b serveboth to ensure electrical contact and to suspend the movementresiliently in the case.

The movement is in addition surrounded by a cage 29 (FIGURES 2 and 5)bearing against the case body denoted by 30. The cage is formed with aninternally threaded hole 31 (FIGURE 5) to receive a screw laterallylocking the plate 1, the object of which screw is to ensure goodelectrical contact between the said plate and the cage 29. The latterhas two passages 32 through which access can be had by means of ascrewdriver to the screws by which the feet (not shown) of the dialdenoted by 33 (FIGURE 2) are secured.

It is to be noted that the accumulator 25 is maintained in position inthe back 26 by a ring 34 of electric'ally insulating material, which isscrewed into an internal screw thread in the ledge 26a of the back 26. Afluid-tight packing 35 is disposed between the accumulator 25 and theback 26. The packing has the object of preventing any electrolyte whichmay escape from the accumulator through the joint 36 between the domes24 and 27 from spreading into the case and more especially from reachingthe movement.

The illustrated watch comprises in addition a terminal for rechargingthe accumulator. The terminal consists of a rod 37 surrounded by aninsulating sleeve 38 which is in turn engaged in a sleeve 39 fitted inthe case body 30. The rod 37 bears at its inner end against an externallug 22d of the casing ring 22, which extends freely into a recess 40 inthe cage 29. When a current source (for example a dry cell) is placed incontact with the outer end of the rod 37, on the one hand, and with thecase on the other hand, the accumulator 25 is recharged, the electricalconnection being effected through the casing ring 22. A detachable cap41 is fixed on the sleeve 39 to prevent the outer end of the rod 37 frombeing accidentally brought into contact with ground, for example bymoisture of the ambient air or by the perspiration of the wearer of thewatch.

Finally, it is to be noted that the hand setting stem of the watch,which is represented only by its axis 42 (FIGURE 1), passes between thetwo parts of the winding by way of a recess (not shown) formed for thispurpose in the insulating packing 7, level with the sleeve 6.

The operation of the illustrated watch is diagrammatically illustratedin FIGURE 6. It will be seen in this figure that with regard to theseries connected accumulator and motor, one of the poles of theaccumulator 25 is connected to ground, while the other pole is connectedto the ring 22 by the lugs 22b of the latter. The lug 22c is connectedto the input terminal of the winding 5, while the output terminal of thelatter is connected to the blades and 16. The latter are grounded whenthe dog 14 is in contact with them and when it applies them against thepins and 21. The dog is in turn connected to ground by the staff 12 ofthe balance wheel and by the spiral spring denoted by 43, because sincethe bearings of the stafi 12 consist of rubies, the staff is notdirectly in contact with the frame of the movement. In this figure, thearmature 11 mount- -ed on the staff 12 of the balance wheel 13 is shownat a distance from the stator, whereas in practice it is pivotallymounted between the pole pieces 3a and 3b above which there extend theends of its vanes 11a to 17a of the insulating packing 7 of the statoris connected in parallel with the winding 5. It has the object ofprotecting the contact formed by the dog 14 and the blades 15 and 16,and it may be replaced by a diode.

What we claim is:

1. In an electric timepiece having a movement wherein an electric motorhas a pair of motor terminals and a stator winding interconnecting saidterminals, a case enclosing said movement, a recharging terminal mountedon said case and electrically insulated from said case, and anaccumulator located within said case and having a pair of accumulatorterminals connected in series electrical circuit with said motor acrosssaid motor terminals, the improvement which includes an electricallyconductive support for said movement within said case and havingresilient lugs electrically conductively supported by one of said pairof accumulator terminals, and said movement having electrical insulationembedding said stator winding and said insulation being engaged withsaid support whereby said movement is supported by said support and saidresilient lugs thereof, electrically insulated from said support, saidsupport being disposed electrically conductively between one of saidpair of motor terminals and said one of said pair of accumulatorterminals as a component of said series electrical circuit, and saidsupport being electrically conductively between said recharging terminaland said one of said accumulator terminals as a conductor for saidaccumulator to be recharged.

2. In an electric timepiece as claimed in claim 1, wherein saidelectrically conductive support includes a lug electrically contactingsaid recharging terminal.

3. In an electric timepiece as claimed in claim 1, wherein the otheraccumulator terminal of said pair of terminals of said accumulator isgrounded to said case, and the other motor terminal of said pair ofmotor terminals is grounded to said case.

4. In an electric timepiece as claimed in claim 1, wherein a cage isdisposed between said movement and said case and is in groundedinterconnection of said other motor terminal of said pair of motorterminals and said case, and said other accumulator terminal of saidpair of accumulator terminals abuts the back of said case in anelectrically grounded relation to said case.

5. In an electric timepiece having a movement wherein an electric motorhas a pair of motor terminals and a stator winding interconnecting saidterminals, a case enclosing said movement, a recharging terminal mountedon said case and electrically insulated from said case, and anaccumulator located within said case and having a pair of accumulatorterminals connected in series electrical circuit with said motor acrosssaid motor terminals, the improvement which includes an electricallyconductive casing ring surrounding said movement within said case andhaving resilient lugs electrically conductively supported by one of saidpair of accumulator terminals, and said movement having electricalinsulation embedding said stator winding and said insulation beingengaged with said casing ring whereby said movement is supported by saidring and said resilient lugs thereof, electrically insulated from saidcasing ring, said casing ring being disposed electrically conductivelybetween one of said pair of motor terminals and said one of said pair ofaccumulator terminals as a component of said series electrical circuit,and said casing ring being electrically conductively between saidrecharging terminal and said one of said accumulator terminals as aconductor for said accumulator to be recharged.

6. In an electric timepiece having a movement wherein an electric motorhas a pair of motor terminals and a stator winding interconnecting saidterminals, said winding being on a stator core of said motor, a caseenclosing said movement, a recharging terminal mounted on said case andelectrically insulated from said case, and an accumulator located withinsaid case and having a pair of accumulator terminals connected in serieselectrical circuit with said motor across said motor terminals, theimprovement which includes said stator core having a substantiallycircular curvature and said winding and core co-extending more than interms of length of the core, a substantially circular frame of saidmovement, an electrically conductive substantially circular casing ringsurrounding said frame in a peripherally spaced relation thereto withinsaid case and having resilient lugs electrically conductively supportedby one of said pair of accumulator terminals, and said movement havingelectrical insulation embedding said stator winding and said insulationbeing engaged with said frame and with said casing ring radially outwardfrom said frame whereby said frame is supported in said peripherallyspaced relation to said ring by said insulation, said casing ring beingdisposed electrically conductively between one of said pair of motorterminals and said one of said pair of accumulator terminals as acomponent of said series electrical circuit, and said casing ring beingelectrically conductively between said recharging terminal and said oneof said accumulator terminals as a conductor for said accumulator to berecharged.

7. In an electric timepiece as claimed in claim 6, wherein saidinsulation embedding the stator winding has an opening receiving ahand-setting stern of said movement through said opening, and saidstator winding is in two sections in series and said sections are disposed on opposite sides of said opening.

8. [In an electric timepiece having a movement wherein an electric motorhas a pair of motor terminals and a stator Winding interconnecting saidterminals, a case enclosing said movement, a recharging terminal mountedon said case and electrically insulated from said case, and anaccumulator located within said case and having a pair of accumulatorterminals connected in series electrical circuit With said motor acrosssaid motor terminals, the improvement which includes an electricallyconductive casing ring surrounding said movement within said case, saidcasing ring having resilient internal lugs electrically conductivelysupported by one of said pair of accumulator terminals and having anexternal terminal lug and an internal terminal lug, and said movementhaving electrical insulation embedding said stator winding and saidinsulation being engaged with said casing ring whereby said movement issupported by said ring and said resilient lugs thereof electricallyinsulated from said casing ring, said internal terminal lug beingelectrically conductively connected with one of said pair of motorterminals placing said ring in said series electrical circuit, and saidexternal terminal lug being electrically oonductively connected withsaid recharging terminal making said ring a conductor for saidaccumulator to be recharged.

References (Iited in the file of this patent UNITED STATES PATENTS2,730,634 De Saint-Vaulry Jan. 10, 1956 2,791,732 Jones May 7,, 19572,907,810 Detwiler et al. Oct. 6, 1959 2,916,871 Wegner Dec. 15, 19592,938,327 Vogel May 31, 1960 FOREIGN PATENTS 1,058,942 Germany June 4,1959

